"Every artist must be free to create work that expresses what he or she believes and not be forced to express contrary views," said ADF Senior Counsel Kristen Waggoner in a statement. "Forcing Americans to promote ideas against their will undermines our constitutionally protected freedom of expression and our right to live free. If the government can take away our First Amendment freedoms, there is nothing it can't take away."

In 2012, Charlie Craig and David Mullins asked Phillips to make a cake for their wedding reception. The couple planned to marry in Massachusetts then hold their reception in Colorado, where same-sex marriages are not recognized.

Phillips, a Christian, told the couple he would make them other baked items but, because of his religious beliefs, could not make them a cake for their wedding celebration.

Craig and Mullins, who are being represented by the ACLU of Colorado, filed a complaint with the Colorado Civil Rights Division, which determined that Masterpiece Cakeshop had illegally discriminated against them. According to the ACLU, the CCRD's findings then led the Colorado Attorney General's office to file a formal complaint against the company with the state courts.

"The undisputed facts show that respondents (Phillips) discriminated against complainants because of their sexual orientation by refusing to sell them a wedding cake for their same-sex marriage," wrote Administrative Law Judge Robert N. Spencer in his decision in December.

Attorneys for Phillips argue that he did not deny the couple a wedding cake "because of" their sexual orientation, according to court documents. He did so because of his "unwavering Christian beliefs" about marriage and about how God would feel if he were to participate in or promote a same-sex wedding.

His attorneys also argue that Phillips's right to refuse to make a cake for a gay wedding celebration is protected by the Free Speech and Free Exercise clauses of the First Amendment.

"America was founded on the fundamental freedom of all citizens to live and work without fear of government punishment," said lead counsel Nicolle Martin, an ADF allied attorney, in a statement. "Jack simply exercised the long-cherished freedom to not speak by declining to promote a false view of marriage through his creative work. It's outrageous that the government would turn its guns on Jack and threaten him with a potential jail sentence unless he says and does what the government demands."

A Rasmussen Reports survey conducted in July 2013 focused on another type of wedding vendor, photographers. The survey found that 85 percent of American adults believe a Christian photographer who is opposed to gay marriage on religious grounds should have the right to say no when asked to work a same-sex wedding ceremony, and only eight percent disagree.